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Pre Calculus Math Tutoring

There are common questions that students have in algebra.  We answer here a couple here on the following topics:

 

Factoring ax2 + bx + c

More Practice Problems

Precalculus Videos

 

We are willing to answer other  questions for you.  Click on the "Contact Us" tab above and we will post an answer.

 

More Practice Problems

I need more practice on problems. Where can I find more practice problems?

 

I have two suggestions.  The first is to go to http://www.kutasoftware.com/ and click on "Worksheets" at the top of the page.  Then scroll down the page and click on "Algebra 2 Worksheets".  Pick the topic you want and click on it.  Answers are included with the worksheets.  The second great suggestion is go to https://www.ixl.com/math/precalculus and click on the topic you want to practice.

 

Factoring ax2 + bx + c

My teacher taught us a method she called “guess and check” or “trial and error”. It is so confusing and I have trouble if the coefficients are big especially if the coefficient of the first term is other than 1. Do you know an easy way?

 

Yes, I do. We will use factoring by grouping sometimes called the“box method”.You will look at the factors of ac that add to b.Then factor by grouping or arrange the terms in a box and factor.It works ever time.

Let us look at an example:Factor 2x2 – 15x + 18.Notice a = 2, b = -15, and c = 18.

Step 1: Calculate ac = 36 where b = -15

Step 2:Find the factors of ac = 36.They are:

1 and 36
- 1 and - 36
2 and 18
- 2 and - 18
3 and 12
- 3 and - 12
4 and 9
- 4 and - 9

Step 3: The only pair that adds to – 15 is - 3 and – 12.Write the polynomial as 2x2 3x – 12x+ 18 .

Step 4: Factor by grouping: Put the first two terms in parentheses and the last two terms separated by a plus sign. ( 2x2 – 3x) + ( – 12x+ 18).

Factor a common factor out of the first grouping and a common factor from the last grouping:
x ( 2x – 3) + ( - 6) ( 2x - 3).(Notice we factored (- 6) from the last two terms.)

Then your answer is (x – 6 )( 2x – 3)

 

Example on your own:

Do you want to try one?Factor 3x2 + 10x – 8 following the steps above.

Solution:The product of ac = -24 and the factors you should have selected were - 2 and 12.

The polynomial you will then factor by grouping is 3x2 – 2x + 12x – 8 .

Your solution after factoring by grouping is (3x – 2)(x + 4).

 

Precalculus Videos

Michael asks, "Are there good algebra review and pre calculus videos?"

 

Michael, there are great precalculus and algebra videos at Khan Academy.  Click on http://www.khanacademy.org/.  Click on "Subjects" at the top and highlight "Math" from the drop down menu.  Then highlight and click on one of the following topics at the right:

Precalculus: Videos of the more common precalculus topics students want help with. 

Trigonometry: Includes videos of some basic trigonometric topics.

Algebra I: Sample problems worked from Algebra I.

 

Another option at Khan Academy is to type your topic in the Seach area to the right of the "Subjects" drop down button.

 

Michael, this is another great site: Go to www.ck12.org/  and click on "Trigonometry" or "Analysis" under Math.  There are great videos and great worked examples.

 

STILL NEED HELP?  Our tutors are here to help you.  Just contact us right now for help.  Either register and log in at the left or click on the Contact Tab at the top of the page!  BOOK YOUR FREE CONSULTATION RIGHT NOW!